var MyHashSet = function () {
    this.map = new Array(1000000 + 1)
};

/** 
 * @param {number} key
 * @return {void}
 */
MyHashSet.prototype.add = function (key) {
    this.map[key] = 1
};

/** 
 * @param {number} key
 * @return {void}
 */
MyHashSet.prototype.remove = function (key) {
    this.map[key] = 0
};

/** 
 * @param {number} key
 * @return {boolean}
 */
MyHashSet.prototype.contains = function (key) {
    return this.map[key] == true
};

/**
 * Your MyHashSet object will be instantiated and called as such:
 * var obj = new MyHashSet()
 * obj.add(key)
 * obj.remove(key)
 * var param_3 = obj.contains(key)
 */